Genome-scale chromatin binding dynamics of RNA Polymerase II general transcription machinery components.

A great deal of work has revealed, in structural detail, the components of the preinitiation complex (PIC) machinery required for initiation of mRNA gene transcription by RNA polymerase II (Pol II). However, less-well understood are the in vivo PIC assembly pathways and their kinetics, an understanding of which is vital for determining how rates of in vivo RNA synthesis are established. We used competition ChIP in budding yeast to obtain genome-scale estimates of the residence times for five general transcription factors (GTFs): TBP, TFIIA, TFIIB, TFIIE and TFIIF. While many GTF-chromatin interactions were short-lived ( < 1 min), there were numerous interactions with residence times in the range of several minutes. Sets of genes with a shared function also shared similar patterns of GTF kinetic behavior. TFIIE, a GTF that enters the PIC late in the assembly process, had residence times correlated with RNA synthesis rates. The datasets and results reported here provide kinetic information for most of the Pol II-driven genes in this organism, offering a rich resource for exploring the mechanistic relationships between PIC assembly, gene regulation, and transcription.

Importance of internal vaginal pelvic floor muscle exams for women with external lumbar/hip/pelvic girdle pain.

INTRODUCTION AND HYPOTHESIS: The relationship between external lumbar, hip, and/or pelvic girdle pain and internal vaginal pelvic floor myofascial pain is not well described. We assessed this relationship in a cohort of adult women. METHODS: The cohort included women ≥ 18 years old who received care for external lumbar, hip, and/or pelvic girdle pain (reported or elicited on physical examination) who then underwent internal vaginal myofascial levator ani pain assessments, in a tertiary care Female Pelvic Medicine and Reconstructive Surgery pelvic pain clinic over a 2-year period (2013 and 2014). RESULTS: The cohort of 177 women had an average age of 44.9±16.0 years, an average body mass index of 27.2±7.0 kg/m2, and the majority (79.2%) were white. Most patients presented with a chief complaint of pelvic (51.4%), vulvovaginal (18.6%), and/or lumbar (15.3%) pain. Women who reported symptoms of lumbar, hip, or pelvic girdle pain were more likely to have pain on vaginal pelvic floor muscle examination than women without this history (OR, 7.24; 95% CI, 1.95-26.93, p=0.003). The majority (85.9%) of women had bilateral internal vaginal pelvic floor myofascial pain on examination. CONCLUSIONS: Although participants did not describe "vaginal pelvic floor myofascial pain," the high detection rate for internal vaginal pelvic floor myofascial pain on clinical examination highlights an opportunity to improve treatment planning. These findings suggest that the vaginal pelvic floor muscle examination should be part of the assessment of all women with lumbar, hip, and/or pelvic girdle pain. The relationship between this finding and clinical outcomes following directed treatment warrants additional study.

The yeast Dbf4 Zn2+ finger domain suppresses single-stranded DNA at replication forks initiated from a subset of origins.

Dbf4 is the cyclin-like subunit for the Dbf4-dependent protein kinase (DDK), required for activating the replicative helicase at DNA replication origin that fire during S phase. Dbf4 also functions as an adaptor, targeting the DDK to different groups of origins and substrates. Here we report a genome-wide analysis of origin firing in a budding yeast mutant, dbf4-zn, lacking the Zn2+ finger domain within the C-terminus of Dbf4. At one group of origins, which we call dromedaries, we observe an unanticipated DNA replication phenotype: accumulation of single-stranded DNA spanning ± 5kbp from the center of the origins. A similar accumulation of single-stranded DNA at origins occurs more globally in pri1-m4 mutants defective for the catalytic subunit of DNA primase and rad53 mutants defective for the S phase checkpoint following DNA replication stress. We propose the Dbf4 Zn2+ finger suppresses single-stranded gaps at replication forks emanating from dromedary origins. Certain origins may impose an elevated requirement for the DDK to fully initiate DNA synthesis following origin activation. Alternatively, dbf4-zn may be defective for stabilizing/restarting replication forks emanating from dromedary origins during replication stress.

Meaningful associations in the adolescent brain cognitive development study.

The Adolescent Brain Cognitive Development (ABCD) Study is the largest single-cohort prospective longitudinal study of neurodevelopment and children's health in the United States. A cohort of n = 11,880 children aged 9-10 years (and their parents/guardians) were recruited across 22 sites and are being followed with in-person visits on an annual basis for at least 10 years. The study approximates the US population on several key sociodemographic variables, including sex, race, ethnicity, household income, and parental education. Data collected include assessments of health, mental health, substance use, culture and environment and neurocognition, as well as geocoded exposures, structural and functional magnetic resonance imaging (MRI), and whole-genome genotyping. Here, we describe the ABCD Study aims and design, as well as issues surrounding estimation of meaningful associations using its data, including population inferences, hypothesis testing, power and precision, control of covariates, interpretation of associations, and recommended best practices for reproducible research, analytical procedures and reporting of results.

Early adolescent gender diversity and mental health in the Adolescent Brain Cognitive Development study.

BACKGROUND: There are known associations between mental health symptoms and transgender identity among adults. Whether this relationship extends to early adolescents and to gender domains other than identity is unclear. This study measured dimensions of gender in a large, diverse, sample of youth, and examined associations between diverse gender experiences and mental health. METHODS: The ABCD study is an ongoing, longitudinal, US cohort study. Baseline data (release 2.0) include 11,873 youth age 9/10 (48% female); and the 4,951 1-year follow-up visits (age 10/11; 48% female) completed prior to data release. A novel gender survey at the 1-year visit assessed felt-gender, gender noncontentedness, and gender nonconformity using a 5-point scale. Mental health measures included youth- and parent-reports. RESULTS: Roughly half a percent of 9/10-year-olds (n = 58) responded 'yes' or 'maybe' when asked, 'Are you transgender' at baseline. Recurrent thoughts of death were more prevalent among these youth compared to the rest of the cohort (19.6% vs. 6.4%, χ2  = 16.0, p < .001). At the 1-year visit, when asked about the three dimensions of gender on a 5-point scale, 33.2% (n = 1,605) provided responses that were not exclusively and totally aligned with one gender. Significant relationships were observed between mental health symptoms and gender diversity for all dimensions assessed. CONCLUSIONS: Similar to adult studies, early adolescents identifying as transgender reported increased mental health symptoms. Results also point to considerable diversity in other dimensions of gender (felt-gender, gender noncontentedness, gender nonconformity) among 10/11-year-olds, and find this diversity to be related to critical mental health symptoms. These findings add to our limited understanding of the relationship between dimensions of gender and wellness for youth.

Second-generation method for analysis of chromatin binding with formaldehyde-cross-linking kinetics.

Formaldehyde-cross-linking underpins many of the most commonly used experimental approaches in the chromatin field, especially in capturing site-specific protein-DNA interactions. Extending such assays to assess the stability and binding kinetics of protein-DNA interactions is more challenging, requiring absolute measurements with a relatively high degree of physical precision. We previously described an experimental framework called the cross-linking kinetics (CLK) assay, which uses time-dependent formaldehyde-cross-linking data to extract kinetic parameters of chromatin binding. Many aspects of formaldehyde behavior in cells are unknown or undocumented, however, and could potentially affect CLK data analyses. Here, we report biochemical results that better define the properties of formaldehyde-cross-linking in budding yeast cells. These results have the potential to inform interpretations of "standard" chromatin assays, including chromatin immunoprecipitation. Moreover, the chemical complexity we uncovered resulted in the development of an improved method for measuring binding kinetics with the CLK approach. Optimum conditions included an increased formaldehyde concentration and more robust glycine-quench conditions. Notably, we observed that formaldehyde-cross-linking rates can vary dramatically for different protein-DNA interactions in vivo Some interactions were cross-linked much faster than the in vivo macromolecular interactions, making them suitable for kinetic analysis. For other interactions, we found the cross-linking reaction occurred on the same time scale or slower than binding dynamics; for these interactions, it was sometimes possible to compute the in vivo equilibrium-binding constant but not binding on- and off-rates. This improved method yields more accurate in vivo binding kinetics estimates on the minute time scale.

Break-seq reveals hydroxyurea-induced chromosome fragility as a result of unscheduled conflict between DNA replication and transcription.

We have previously demonstrated that in Saccharomyces cerevisiae replication, checkpoint inactivation via a mec1 mutation leads to chromosome breakage at replication forks initiated from virtually all origins after transient exposure to hydroxyurea (HU), an inhibitor of ribonucleotide reductase. Here we sought to determine whether all replication forks containing single-stranded DNA gaps have equal probability of producing double-strand breaks (DSBs) when cells attempt to recover from HU exposure. We devised a new methodology, Break-seq, that combines our previously described DSB labeling with next generation sequencing to map chromosome breaks with improved sensitivity and resolution. We show that DSBs preferentially occur at genes transcriptionally induced by HU. Notably, different subsets of the HU-induced genes produced DSBs in MEC1 and mec1 cells as replication forks traversed a greater distance in MEC1 cells than in mec1 cells during recovery from HU. Specifically, while MEC1 cells exhibited chromosome breakage at stress-response transcription factors, mec1 cells predominantly suffered chromosome breakage at transporter genes, many of which are the substrates of those transcription factors. We propose that HU-induced chromosome fragility arises at higher frequency near HU-induced genes as a result of destabilized replication forks encountering transcription factor binding and/or the act of transcription. We further propose that replication inhibitors can induce unscheduled encounters between replication and transcription and give rise to distinct patterns of chromosome fragile sites.

Effect of oral trazodone on the minimum alveolar concentration of isoflurane in dogs.

OBJECTIVE: To determine the effect of oral trazodone on the minimum alveolar concentration (MAC) of isoflurane in dogs. STUDY DESIGN: Prospective blinded, single-observer, randomized crossover experimental study. ANIMALS: Six adult (age 6.8 ± 1.6 months) healthy dogs (three males and three females), weighing 24.8 ± 3.4 kg (mean ± standard deviation). METHODS: Each dog was anesthetized twice with a minimum of 7 days between anesthetic episodes. Dogs were randomly assigned to be administered two treatments in a crossover design: premedication with trazodone (8 mg kg-1; TRAZ-ISO) orally 2 hours prior to an anesthetic episode or no (ISO). Dogs were anesthetized with intravenous propofol (6 mg kg-1) and isoflurane in >95% oxygen. Isoflurane MAC was determined using an iterative bracketing technique with electrodes placed in the buccal mucosa. Hemodynamic variables were compared at the lowest end-tidal isoflurane concentration at which each dog did not respond. A paired t test was used to assess the effect of treatment on outcome variables with significance set to a value of p < 0.05. RESULTS: The MAC concentration (mean ± standard deviation) in dogs administered TRAZ-ISO was 0.85 ± 0.17% compared with 1.02 ± 0.11% in those administered ISO (p = 0.01, 95% confidence interval -0.25 to -0.05), resulting in a mean MAC reduction of 17 ± 12%. There were no differences in hemodynamic variables between treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Premedication of dogs with oral trazodone (8 mg kg-1) 2 hours prior to anesthetic induction has a significant isoflurane MAC sparing effect with no significant observed hemodynamic benefit.

Formaldehyde crosslinking: a tool for the study of chromatin complexes.

Formaldehyde has been used for decades to probe macromolecular structure and function and to trap complexes, cells, and tissues for further analysis. Formaldehyde crosslinking is routinely employed for detection and quantification of protein-DNA interactions, interactions between chromatin proteins, and interactions between distal segments of the chromatin fiber. Despite widespread use and a rich biochemical literature, important aspects of formaldehyde behavior in cells have not been well described. Here, we highlight features of formaldehyde chemistry relevant to its use in analyses of chromatin complexes, focusing on how its properties may influence studies of chromatin structure and function.

Atp13a2-deficient mice exhibit neuronal ceroid lipofuscinosis, limited α-synuclein accumulation and age-dependent sensorimotor deficits.

Mutations in ATP13A2 (PARK9), encoding a lysosomal P-type ATPase, are associated with both Kufor-Rakeb syndrome (KRS) and neuronal ceroid lipofuscinosis (NCL). KRS has recently been classified as a rare genetic form of Parkinson's disease (PD), whereas NCL is a lysosomal storage disorder. Although the transport activity of ATP13A2 has not been defined, in vitro studies show that its loss compromises lysosomal function, which in turn is thought to cause neuronal degeneration. To understand the role of ATP13A2 dysfunction in disease, we disrupted its gene in mice. Atp13a2(-/-) and Atp13a2(+/+) mice were tested behaviorally to assess sensorimotor and cognitive function at multiple ages. In the brain, lipofuscin accumulation, α-synuclein aggregation and dopaminergic pathology were measured. Behaviorally, Atp13a2(-/-) mice displayed late-onset sensorimotor deficits. Accelerated deposition of autofluorescent storage material (lipofuscin) was observed in the cerebellum and in neurons of the hippocampus and the cortex of Atp13a2(-/-) mice. Immunoblot analysis showed increased insoluble α-synuclein in the hippocampus, but not in the cortex or cerebellum. There was no change in the number of dopaminergic neurons in the substantia nigra or in striatal dopamine levels in aged Atp13a2(-/-) mice. These results show that the loss of Atp13a2 causes sensorimotor impairments, α-synuclein accumulation as occurs in PD and related synucleinopathies, and accumulation of lipofuscin deposits characteristic of NCL, thus providing the first direct demonstration that null mutations in Atp13a2 can cause pathological features of both diseases in the same organism.

Analysis of chromatin binding dynamics using the crosslinking kinetics (CLK) method.

Transcription factor binding sites in chromatin are routinely inventoried by the chromatin immunoprecipitation assay, and these binding patterns can provide precise and detailed information about cell state. However, some fundamental molecular questions regarding transcription factor function require an understanding of in vivo binding dynamics as well as location information. Here we describe the crosslinking kinetics (CLK) assay, in which the time-dependence of formaldehyde crosslinking is used to extract on- and off-rates for chromatin binding in vivo.

The metabolic syndrome.

The metabolic syndrome is a constellation of signs and symptoms which increase a patient's risk of developing heart disease and diabetes mellitus. The metabolic syndrome or syndrome X includes central obesity, hypertension, hyperglycemia, and dyslipidemia. Diagnosing the metabolic syndrome in a patient identifies areas that can be addressed and with appropriate treatment can lower the risk of diabetes and cardiovascular disease. One area of controversy is the question: does the metabolic syndrome as a whole increase risk more than the sum of its parts? Recognizing the metabolic syndrome early with treatment can improve our patients' long-term health.

NURTURE: development and pilot testing of a novel parenting intervention for mothers with histories of an eating disorder.

OBJECTIVE: To describe the treatment development and pilot testing of a group parenting intervention, NURTURE (Networking, Uniting, and Reaching out To Upgrade Relationships and Eating), for mothers with histories of eating disorders. METHOD: Based on focus group findings, extant research, and expert opinion, NURTURE was designed to be delivered weekly over 16 (1.5 h) sessions via an interactive web conferencing forum. It comprises four modules: (1) laying the foundation, (2) general parenting skills, (3) eating and feeding, and (4) breaking the cycle of risk. Pilot testing was conducted with three groups of 3-6 mothers (N = 13) who had children ages 0-3 years to determine feasibility (e.g., retention), acceptability (e.g., feedback questionnaire responses), and preliminary efficacy. Maternal satisfaction with NURTURE and changes in mother-child feeding relationship measures, maternal feeding style, maternal self-efficacy, and maternal psychopathology (eating disorder, depression, and anxiety symptoms) across three time points (baseline, post-treatment, 6-month follow-up) were examined. All outcomes were exploratory. RESULTS: The intervention was well tolerated with a 100% retention rate. Feedback from mothers was generally positive and indicated that the groups provided an engaging, supportive experience to participants. We observed changes suggestive of improvement in self-reported maternal self-efficacy and competence with parenting. There were no notable changes in measures of maternal feeding style or psychopathology. DISCUSSION: NURTURE is a feasible, acceptable, and potentially valuable intervention for mothers with eating disorder histories. Results of this pilot will inform a larger randomized-controlled intervention to determine efficacy and impact on child outcomes.

A comparison of infant and toddler feeding practices of mothers with and without histories of eating disorders.

This preliminary study surveyed the feeding practices of mothers with eating disorder histories through evaluation of mothers' reported feeding styles, child diet composition and restrictive special approaches to feeding. For this non-randomised cohort study, 25 mothers with eating disorder histories and 25 mothers with no history of an eating disorder with children ages 6-36 months were selected such that the groups were similar based on child age group and child sex. Mothers were compared on self-reported feeding style using the Infant Feeding Styles Questionnaire and on child diet composition and special feeding approaches using a modified version of the Toddler Diet Questionnaire from the Women, Infants, and Children program. Mothers with eating disorder histories scored lower on the restrictive feeding style subscale than controls. No significant differences were detected between groups in child diet including the percentage of mothers who breastfed, duration of breastfeeding, age at solid food introduction, daily number of meals or snacks or daily frequency of consumption of fruits, vegetables or protein foods. Mothers with eating disorder histories were more likely to report taking a restrictive special approach to feeding such as limiting processed foods or feeding organic foods only. Although mothers with eating disorder histories may not differ greatly from control mothers in terms of child diet composition (smaller effects may not have been detected due to limited sample size), they may be more likely to take restrictive special approaches to feeding which mirror dietary rules common in individuals with eating disorders.

Outcomes After Induction of Labor Compared With Dilation and Evacuation for the Management of Rupture of Membranes in the Second Trimester.

Previable and periviable rupture of membranes is associated with significant morbidity for the pregnant patient. For those who have a choice of options and undergo active management, it is not known how the risks of induction of labor compare with those for dilation and evacuation (D&E). We performed a retrospective cohort study of patients with rupture of membranes between 14 0/7 and 23 6/7 weeks of gestation who opted for active management. Adverse events (52.2% vs 16.9%, P <.01) and time to uterine evacuation greater than 24 hours (26.7% vs 9.6%, P =.01) were more common among patients undergoing induction of labor. In a multivariable regression, induction of labor was an independent risk factor for complications (odds ratio 5.70, 95% CI, 2.35-13.82) compared with D&E. Severe complications were rare across both groups (4.4% for patients undergoing induction vs 2.6% for D&E, P =.63). Given the differing risks by termination method, access to D&E is an important treatment option for this patient population.

Connectome-based Brain Marker Moderates the Relationship between Childhood Adversity and Transdiagnostic Psychopathology during Early Adolescence.

Importance: Identifying brain-based markers of resiliency that reliably predict who is and is not at elevated risk for developing psychopathology among children who experience adverse childhood experiences (ACEs) is important for improving our mechanistic understanding of these etiological links between child adversity and psychopathology and guiding precision medicine and prevention efforts for reducing psychiatric impact of ACEs. Objective: To examine associations between ACEs and transdiagnostic psychopathology during the transition from preadolescence to early adolescence and test whether these associations are moderated by a hypothesized resilience factor, a previously identified connectome variate (CV) that is associated with higher cognitive function and lower psychopathology. Design Setting and Participants: This study was conducted in a longitudinal design based on multicenter data from a community cohort of U.S. youth aged of 9-11 at baseline, who participated in the Adolescent Brain Cognitive Development (ABCD) study (N=7,382 at baseline and 6,813 at 2-year follow-up). Linear regression models and moderation analyses were used to characterize concurrent and prospective associations between lifetime ACEs and number of DSM-5 psychiatric disorders (indexing transdiagnostic psychopathology) and to determine if individual variations in these associations were moderated by the CV derived from resting-state fMRI at baseline. Main Outcomes and Measures: Cumulative number of current DSM-5 psychiatric disorders assessed using the computerized self-admin version Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS-5) and lifetime ACEs assessed from child and parent reports at baseline (9-10 years) and 2-year-follow-up (11-12 years). Results: ACE total scores correlated positively with the cumulative number of current DSM-5 psychiatric disorders at both baseline (r =.258, p < .001) and 2-year follow-up (r =.257, p < .001). The baseline CV score moderated the ACE-disorder associations at baseline (B = -0.021, p < .001) and at 2-year follow-up (B = -0.018, p = .008), as well as the association between the changes in ACE and in the number of disorders from baseline to year 2 (B = -0.012, p = .045). Post-hoc analyses further showed that the moderation effect of CV on ACE-psychopathology associations was specific to the threat-related ACEs and to female youth. Conclusions and Relevance: These findings provide preliminary evidence for a connectome-based resiliency marker and suggest that functional connectivity strength in a broad system including frontal-parietal cortices and subcortical nuclei relevant to cognitive control may protect preadolescents who have experienced lifetime ACEs--especially females and those experiencing threat-related ACEs--from developing transdiagnostic psychopathology.

Genome-scale chromatin interaction dynamic measurements for key components of the RNA Pol II general transcription machinery.

Background: A great deal of work has revealed in structural detail the components of the machinery responsible for mRNA gene transcription initiation. These include the general transcription factors (GTFs), which assemble at promoters along with RNA Polymerase II (Pol II) to form a preinitiation complex (PIC) aided by the activities of cofactors and site-specific transcription factors (TFs). However, less well understood are the in vivo PIC assembly pathways and their kinetics, an understanding of which is vital for determining on a mechanistic level how rates of in vivo RNA synthesis are established and how cofactors and TFs impact them. Results: We used competition ChIP to obtain genome-scale estimates of the residence times for five GTFs: TBP, TFIIA, TFIIB, TFIIE and TFIIF in budding yeast. While many GTF-chromatin interactions were short-lived (< 1 min), there were numerous interactions with residence times in the several minutes range. Sets of genes with a shared function also shared similar patterns of GTF kinetic behavior. TFIIE, a GTF that enters the PIC late in the assembly process, had residence times correlated with RNA synthesis rates. Conclusions: The datasets and results reported here provide kinetic information for most of the Pol II-driven genes in this organism and therefore offer a rich resource for exploring the mechanistic relationships between PIC assembly, gene regulation, and transcription. The relationships between gene function and GTF dynamics suggest that shared sets of TFs tune PIC assembly kinetics to ensure appropriate levels of expression.

Mgm101 is a Rad52-related protein required for mitochondrial DNA recombination.

Homologous recombination is a conserved molecular process that has primarily evolved for the repair of double-stranded DNA breaks and stalled replication forks. However, the recombination machinery in mitochondria is poorly understood. Here, we show that the yeast mitochondrial nucleoid protein, Mgm101, is related to the Rad52-type recombination proteins that are widespread in organisms from bacteriophage to humans. Mgm101 is required for repeat-mediated recombination and suppression of mtDNA fragmentation in vivo. It preferentially binds to single-stranded DNA and catalyzes the annealing of ssDNA precomplexed with the mitochondrial ssDNA-binding protein, Rim1. Transmission electron microscopy showed that Mgm101 forms large oligomeric rings of ∼14-fold symmetry and highly compressed helical filaments. Specific mutations affecting ring formation reduce protein stability in vitro. The data suggest that the ring structure may provide a scaffold for stabilization of Mgm101 by preventing the aggregation of the otherwise unstable monomeric conformation. Upon binding to ssDNA, Mgm101 is remobilized from the rings to form distinct nucleoprotein filaments. These studies reveal a recombination protein of likely bacteriophage origin in mitochondria and support the notion that recombination is indispensable for mtDNA integrity.

Understanding the association of impulsivity, obsessions, and compulsions with binge eating and purging behaviours in anorexia nervosa.

OBJECTIVE: To further refine our understanding of impulsivity, obsessions, and compulsions in anorexia nervosa (AN) by isolating which behaviours--binge eating, purging, or both--are associated with these features. METHODS: We conducted regression analyses with binge eating, purging, and the interaction of binge eating with purging as individual predictors of scores for impulsivity, obsessions, and compulsions in two samples of women with AN (n = 1373). RESULTS: Purging, but not binge eating, was associated with higher scores on impulsivity, obsessions, and compulsions. Purging was also associated with worst eating rituals and with worst eating preoccupations. CONCLUSION: Our results suggest that purging, compared with binge eating, may be a stronger correlate of impulsivity, obsessions, and compulsions in AN.